The overall aim of the proposed program is to develop, fabricate and clinically test an easy-to-use affordable diagnostic instrument that can non-invasively detect subsurface inflammations and estimate the temperatures of such inflammations. The design of this instrument will be based on a novel fast-reading, self-calibrating, dual-frequency digital radiometer developed under an SBIR grant from NIH for use in two-dimensional eonformal hyperthermia array antennas. By taking advantage of recent advances in micro-miniaturization of microwave devices, the front-end of the radiometer will be integrated with the receiving antenna. This will simplify the radiometer circuitry, increase its sensitivity, and reduce calibration and acquisition times. The examining health professional will be able to move the small, integrated antenna assembly (Thermoscope) to any point on the body of a patient with the same ease as moving a stethoscope and quickly and accurately determine skin temperatures and two subsurface tissue temperatures averaged over two different tissue depth. The specific aims of the proposed Phase I program are to design, fabricate and test an experimental model of a Thermoseope equipped self-calibrating diagnostic dual-frequency digital microwave radiometer and write software for the radiometer that will enhance its diagnostic uefulness.